AUSTIN — Up to 1,000 National Guard troops are headed to Texas' southern border to help collar criminals, as thousands of undocumented youth continue to migrate illegally over the border.

The troops from the Texas National Guard will be backing agents sent down earlier this year by the Texas Department of Public Safety, or DPS, Texas Gov. Rick Perry said at a press conference Monday. The Guardsmen will be helping to hunt down drug cartels, smuggling rings and other criminal elements, both with on-the-ground patrols and aerial reconnaissance, he said.

Unlike previous times where Guardsmen were dispatched to the border, the troops this time around will be backing DPS in search for criminals, not working alongside with Border Patrol agents, Perry said.

More than 3,000 Border Patrol agents currently work in the region, and Perry has repeatedly asked President Obama to send the National Guard to the border. The region has been overwhelmed in recent months by unaccompanied children illegally entering the USA. He's also asked the government to repay about $500 million the state has spent on securing its border in recent years.

"The price of inaction is too high for Texas to pay," Perry said.

The White House hadn't yet received formal notification that Texas was deploying the National Guard, Press Secretary Josh Earnest said Monday.

"If this deployment does move forward, it is the kind of step that we would like to see be coordinated and integrated with the ongoing response there," Earnest said, noting that Obama signaled his openness to the idea when he met with Gov. Perry two weeks ago.

Perry, widely expected to run for president in 2016, has been at the center of the controversy, calling on the federal government to do more to secure its border with Mexico and repatriate the children.

Last month, Perry and other Texas officials called on DPS to deploy more agents to the border — at a cost of $1.3 million a week. Along with the National Guard contingent, the new initiatives will cost Texas about $5 million a week.

Since 2008, more than 203,000 criminal aliens have been booked into Texas county jails, Perry said.

"I will not stand idly by while our citizens are under assault and little children from Central America are detained in squalor," he said.

Monday's announcement comes as an unprecedented wave of unaccompanied minors continues crossing illegally into the USA, most of them across Texas' border. More than 57,000 of the youth have crossed over this fiscal year, more than double that of last year, overwhelming federal facilities and Border Patrol agents. The youth, mostly from Guatemala, Honduras and El Salvador, are often fleeing gang violence or economic hardships in their countries.

The White House says those numbers have been declining, however. In June, the Customs and Border Patrol picked up an average of 355 unaccompanied children per day in the Rio Grande Valley. This month, it's dropped to 150 a day, according to preliminary data. Earnest attributed the drop to a U.S. publicity campaign in Central America and to a seasonal drop in the summer.

Obama's recent request for $3.7 billion in emergency funding to deal with the crisis was met with skepticism by Republican lawmakers in Washington, who are crafting their own proposal to deal with the situation that will include swifter deportations of the youth.

In a White House letter to Perry on July 7, Obama adviser, Valerie Jarrett, laid out steps the administration was taking to deal with what the president had called an "urgent humanitarian situation," but did not mention the National Guard. Obama met with Perry two days later in Dallas, and the administration has worked with Mexico and other countries the immigrants are leaving to make it clear they will not be allowed to stay in the U.S.

The National Guard troops could deter future immigrants from taking the treacherous journey north and, more important, help law enforcement agents crack down on criminal smuggling rings and drug cartels that could be infiltrating the USA's border amid the crisis, said George Grayson, a Mexico expert at the College of William and Mary in Williamsburg, Va., who has written about border security.

"Given the fact that so many Border Patrol agents have to do so many ancillary activities, having another cadre there is a step in the right direction," Grayson said.

But Tony Payan, director of the Mexico Center at Rice University's James A. Baker Institute for Public Policy, called the move "political theater" by Perry. Putting more troops on the border, especially those who can't legally arrest immigrants, detracts from the larger issue of why the youth are fleeing their countries in the first place, he said.

"It's the wrong medicine for the problem," Payan said. "This is a much larger transnational issue."

In 2006, then-president George W. Bush deployed 6,000 National Guard troops to the Southwest border, but that number dwindled over the years to a few hundred due to budget cutbacks. Unlike that scenario, the Guardsmen this time around are expected to back up DPS agents, not Border Patrol agents. They could detain people crossing over illegally but cannot arrest them, said Texas Adjutant General John Nichols.

On those previous border deployments, the National Guard soldiers served in support roles — administrative, intelligence-gathering — while the Border Patrol expanded its ranks. Some National Guard troops already participate in counter-drug operations on the border, though they don't have arrest powers.